<template>
    <div>
      <!-- 面包屑导航区域 -->
      <el-breadcrumb separator-class="el-icon-arrow-right">
        <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
        <el-breadcrumb-item>商品管理</el-breadcrumb-item>
        <el-breadcrumb-item>参数列表</el-breadcrumb-item>
      </el-breadcrumb>

      <!--   卡片视图区域   -->
      <el-card>
        <!--    警告区域    -->
        <el-alert
          show-icon
          title="注意：只允许为第三级分类设置相关参数！"
          type="warning"
          :closable="false"></el-alert>

        <!--    选择商品分类区域    -->
        <el-row class="cat_opt">
          <el-col>
            <span>选择商品分类：</span>
            <!--     选择商品分类的级联选择框     -->
            <el-cascader
              expand-trigger="hover"
              v-model="selectedCateKeys"
              :options="catelist"
              :props="cateProps"
              @change="handleChange"></el-cascader>
          </el-col>
        </el-row>

        <!--    tab 页签区域    -->
        <el-tabs v-model="activeName" @tab-click="handleTabClick">
          <!--    添加动态参数的面板      -->
          <el-tab-pane label="动态参数" name="many">
            <!--      添加参数的按钮      -->
            <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加参数</el-button>
            <!--     动态参数表格       -->
            <el-table :data="manyTableData" border stripe>
              <!--     展开行       -->
              <el-table-column type="expand">
                <template slot-scope="scope">
                  <!--     循环渲染Tag标签       -->
                  <el-tag
                    v-for="(item,i) in scope.row.attr_vals"
                    :key="i"
                    closable
                    @close="handleClose(i,scope.row)">{{item}}</el-tag>
                  <!--     输入的文本框       -->
                  <el-input
                    class="input-new-tag"
                    v-if="scope.row.inputVisible"
                    v-model="scope.row.inputValue"
                    ref="saveTagInput"
                    size="small"
                    @keyup.enter.native="handleInputConfirm(scope.row)"
                    @blur="handleInputConfirm(scope.row)">
                  </el-input>
                  <!--     添加按钮       -->
                  <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
                </template>
              </el-table-column>
              <!--     索引列       -->
              <el-table-column type="index"></el-table-column>
              <el-table-column label="参数名称" prop="attr_name"></el-table-column>
              <el-table-column label="操作">
                <template slot-scope="scope">
                  <el-button size="mini" type="primary" icon="el-icon-edit" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                  <el-button size="mini" type="danger" icon="el-icon-delete" @click="removeParams(scope.row.attr_id)">删除</el-button>
                </template>
              </el-table-column>
            </el-table>
          </el-tab-pane>
          <!--    添加静态参数的面板      -->
          <el-tab-pane label="静态属性" name="only">
            <!--      添加参数的按钮      -->
            <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加参数</el-button>
            <!--     静态属性表格       -->
            <el-table :data="onlyTableData" border stripe>
              <!--     展开行       -->
              <el-table-column type="expand">
                <template slot-scope="scope">
                  <!--     循环渲染Tag标签       -->
                  <el-tag
                    v-for="(item,i) in scope.row.attr_vals"
                    :key="i"
                    closable
                    @close="handleClose(i,scope.row)">{{item}}</el-tag>
                  <!--     输入的文本框       -->
                  <el-input
                    class="input-new-tag"
                    v-if="scope.row.inputVisible"
                    v-model="scope.row.inputValue"
                    ref="saveTagInput"
                    size="small"
                    @keyup.enter.native="handleInputConfirm(scope.row)"
                    @blur="handleInputConfirm(scope.row)">
                  </el-input>
                  <!--     添加按钮       -->
                  <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
                </template>
              </el-table-column>
              <!--     索引列       -->
              <el-table-column type="index"></el-table-column>
              <el-table-column label="属性名称" prop="attr_name"></el-table-column>
              <el-table-column label="操作">
                <template slot-scope="scope">
                  <el-button size="mini" type="primary" icon="el-icon-edit" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                  <el-button size="mini" type="danger" icon="el-icon-delete" @click="removeParams(scope.row.attr_id)">删除</el-button>
                </template>
              </el-table-column>
            </el-table>
          </el-tab-pane>
        </el-tabs>
      </el-card>

      <!--   添加参数的对话框   -->
      <el-dialog
        :title="'添加' + titleText"
        :visible.sync="addDialogVisible"
        width="50%"
        @close="addDialogClosed">
        <!--   添加参数的表单   -->
        <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
          <el-form-item :label="titleText" prop="attr_name">
            <el-input v-model="addForm.attr_name"></el-input>
          </el-form-item>
        </el-form>
        <span slot="footer" class="dialog-footer">
          <el-button @click="addDialogVisible = false">取 消</el-button>
          <el-button type="primary" @click="addParams">确 定</el-button>
        </span>
      </el-dialog>

      <!--   修改参数的对话框   -->
      <el-dialog
        :title="'修改' + titleText"
        :visible.sync="editDialogVisible"
        width="50%"
        @close="editDialogClosed">
        <!--   添加参数的表单   -->
        <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
          <el-form-item :label="titleText" prop="attr_name">
            <el-input v-model="editForm.attr_name"></el-input>
          </el-form-item>
        </el-form>
        <span slot="footer" class="dialog-footer">
          <el-button @click="editDialogVisible = false">取 消</el-button>
          <el-button type="primary" @click="editParams">确 定</el-button>
        </span>
      </el-dialog>
    </div>
</template>

<script>
  export default {
    name: 'Params',
    data(){
      return{
        // 商品分类列表
        catelist:[],
        // 级联选择框的配置对象
        cateProps:{
          value: 'cat_id',
          label: 'cat_name',
          children: 'children'
        },
        // 级联选择框双向绑定的数组
        selectedCateKeys:[],
        // 被激活的页签名称
        activeName:'many',
        // 动态参数的数据
        manyTableData:[],
        // 静态参数的数据
        onlyTableData:[],
        // 控制添加对话框的显示与隐藏
        addDialogVisible: false,
        // 添加参数的表单数据对象
        addForm:{
          attr_name: ''
        },
        // 添加表单的验证规则对象
        addFormRules: {
          attr_name: [{
            required: true,
            message: '请输入参数名称',
            trigger: 'blur'
          }]
        },
        // 控制修改对话框的显示与隐藏
        editDialogVisible: false,
        // 修改参数的表单数据对象
        editForm:{},
        // 修改表单的验证规则对象
        editFormRules: {
          attr_name: [{
            required: true,
            message: '请输入参数名称',
            trigger: 'blur'
          }]
        }
      }
    },
    created () {
      this.getCateList()
    },
    methods:{
      // 获取所有的商品分类列表
      async getCateList(){
        const {data:res} = await this.$http.get('categories')
        if (res.meta.status !== 200){
          return this.$message.error('获取商品分类失败！')
        }

        this.catelist = res.data

        console.log(this.catelist)
      },
      // 级联选择框选中项变化，会触发这个函数
      async handleChange(){
        this.getParamsData()
      },
      // tab 页签点击事件的处理函数
      handleTabClick(){
        console.log(this.activeName)
        this.getParamsData()
      },
      // 获取参数的列表数据
      async getParamsData(){
        // 证明选中的不是三级分类
        if (this.selectedCateKeys.length !== 3){
          this.selectedCateKeys = []
          this.manyTableData = []
          this.onlyTableData = []
          return
        }

        // 证明选中的是三级分类
        console.log(this.selectedCateKeys)
        // 根据所选分类的Id，和当前所处的面板获取对应的参数
        const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes`,{
          params:{
            sel: this.activeName
          }
        })

        if (res.meta.status !== 200){
          return this.$message.error('获取参数列表失败！')
        }

        console.log(res.data)
        res.data.forEach(item=>{
          item.attr_vals = item.attr_vals ? item.attr_vals.split(' '): []
          // 控制文本框的显示与隐藏
          item.inputVisible = false
          // 文本框中输入的值
          item.inputValue = ''
        })
        if (this.activeName === 'many'){
          this.manyTableData = res.data
        }else{
          this.onlyTableData = res.data
        }
      },
      // 监听添加对话框的关闭事件
      addDialogClosed(){
        this.$refs.addFormRef.resetFields()
      },
      // 点击按钮，添加参数
      addParams(){
        this.$refs.addFormRef.validate(async valid =>{
          if (!valid) return
          const {data:res} = await this.$http.post(`categories/${this.cateId}/attributes`,{
            attr_name: this.addForm.attr_name,
            attr_sel: this.activeName
          })

          if (res.meta.status !== 201){
            return this.$message.error('添加参数失败！')
          }

          this.$message.success('添加参数成功！')
          this.addDialogVisible = false
          this.getParamsData()
        })
      },
      // 点击按钮，展示修改的对话框
      async showEditDialog(attr_id){
        // 查询当前参数的信息
        const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes/${attr_id}`,{
          params: {attr_sel: this.activeName}
        })

        if (res.meta.status !== 200){
          return this.$message.error('获取参数失败！')
        }

        this.editForm = res.data
        this.editDialogVisible = true
      },
      // 重置修改的表单
      editDialogClosed(){
        this.$refs.editFormRef.resetFields()
      },
      // 点击按钮，修改参数信息
      editParams(){
        this.$refs.editFormRef.validate(async valid=>{
          if (!valid) return
          const {data:res} = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`,{
            attr_name: this.editForm.attr_name,
            attr_sel: this.activeName
          })

          if (res.meta.status !== 200){
            return this.$message.error('修改参数失败！')
          }

          this.$message.success('修改参数成功！')
          this.getParamsData()
          this.editDialogVisible = false
        })
      },
      // 根据Id删除对应的参数项
      async removeParams(attr_id){
        //  弹框询问用户是否删除数据
        const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        }).catch(err => err)

        // 如果用户确认删除，则返回值为字符串 confirm
        // 如果用户取消了删除，则返回值为字符串 cancel
        // console.log(confirmResult)
        if (confirmResult !== 'confirm'){
          return this.$message.info('已取消删除')
        }
        const {data:res} = await this.$http.delete(`categories/${this.cateId}/attributes/${attr_id}`)

        if (res.meta.status !== 200){
          return this.$message.error('删除参数失败！')
        }
        this.$message.success('删除参数成功！')
        this.getParamsData()
      },
      // 文本框失去焦点，或按下了Enter都会触发
      async handleInputConfirm(row){
        if (row.inputValue.trim().length === 0){
          row.inputValue = ''
          row.inputVisible = false
          return
        }
        // 如果没有return，则证明输入的内容，需要做后续处理
        row.attr_vals.push(row.inputValue.trim())
        row.inputValue = ''
        row.inputVisible = false
        // 需要发起请求，保存这次操作
        this.saveAttrVals(row)
      },
      // 将对 attr_vals 的操作，保存到数据库
      async saveAttrVals(row){
        // 需要发起请求，保存这次操作
        const {data:res} = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`,{
          attr_name: row.attr_name,
          attr_sel: row.attr_sel,
          attr_vals: row.attr_vals.join(' ')
        })

        if (res.meta.status !== 200){
          return this.$message.error('修改参数项失败！')
        }
        this.$message.success('修改参数项成功！')
      },
      // 点击按钮，展示文本输入框
      showInput(row){
        row.inputVisible = true
        // 让文本框自动获取焦点
        // $nextTick 方法的作用，就是当页面上元素被重新渲染之后，才会指定回调函数中的代码
        this.$nextTick(_ =>{
          this.$refs.saveTagInput.$refs.input.focus()
        })
      },
      // 删除对应的参数可选项
      handleClose(i, row){
        row.attr_vals.splice(i, 1)
        this.saveAttrVals(row)
      }
    },
    computed:{
      // 如果按钮需要被禁用，则返回true，否则返回false
      isBtnDisabled(){
        if (this.selectedCateKeys.length !== 3){
          return true
        }
        return false
      },
      // 当前选中的三级分类的Id
      cateId(){
        if (this.selectedCateKeys.length === 3){
          return this.selectedCateKeys[2]
        }
        return null
      },
      // 动态计算标题的文本
      titleText(){
        if (this.activeName === 'many'){
          return '动态参数'
        }
        return '静态属性'
      }
    }
  }
</script>

<style lang="less" scoped>
  .cat_opt{
    margin: 15px 0;
  }

  .el-tag{
    margin: 10px;
  }

  .input-new-tag{
    width: 120px;
  }
</style>
